When you Detect Evil on someone, can they tell you're doing it? Can it be done subtly, or is it going to be noticed? Can the person it is being used on feel it? Does it depend, and if so, on what? In the case of this particular character, I'd certainly say there would be a facial expression of concentration that would show something was going on, but would not necessarily show what, but I'd think others who were more subtle, or wearing a helm, might be able not to show it as much, or at all. When I've seen the power used by others, I've noticed that it is usually accompanied by an emote along the lines of: *stares hard at him for a few moments*.
Is it cheesy to try again immediately or soon after if the person makes their will save? My character has two chances to try this before he's used them up, so my assumption was that it would make sense for him to try again if he could not tell the first time (I am further assuming that if the detect fails the caster does know it failed; that is, they know they can't tell one way or the other), but it does occur to me that if I had ten chances to try this my target might get annoyed if I just kept trying it over and over till it worked. On the other hand, ICly why not use the resources you've got? But on the OTHER other hand...so you see this is why I'm asking!

Further assumptions are that it is perfectly kosher to try again the next day, or several hours later when you meet the person again, and that it is not kosher to detect, rest to get the spell back, and detect again immediately. Let me know if these assumptions are correct, too?
Thanks!